1. Field of the Invention
The present invention relates to a compact hydropower generating apparatus adopting multiple rotary drums, and more particularly, to a compact hydropower generation system having the following advantages: small-sized power generation utilizing a small river; easy installation of a small-scale nonpolluting hydroelectric power plant around the small river wherever there is a gentle gradient while achieving a minimum effect on the ecosystem of the small river; an efficient utilization of installation space with minimum environmental disruption; a considerable reduction in use of fossil fuel and energy; and an improvement in product quality and reliability.
2. Description of the Related Art
For countries suffering from a serious shortage of energy sources and showing a high degree of dependence upon imported energy, it is important to achieve maximum use of existing domestic energy sources for the stabilization of the energy supply. Furthermore, in order to effectively deal with a worldwide restriction due to global warming, it is essential to develop clean energy to bring about an improvement in percentage of energy independence. Nowadays, a compact hydropower resource is highly regarded when compared to other alternative energy resources since it has a high energy density. In Korea, to facilitate the utilization and development of compact hydropower, it is already possible to invest private capital in the development of compact hydropower plants based on the “compact hydropower development plan” (established in 1982). As a result of such positive governmental support, over thirty compact hydropower plants, each having a capacity of approximately 43 MW, had already been developed by the end of October 2003, and thus, approximately 100 GWh of electricity can be generated a year. However, the above mentioned capacity is only about 3.0% of the potential amount. Accordingly, to expand the utilization of small-sized hydropower energy, multilateral efforts—for example, development of related technologies, increased governmental support, promotion of related industries, and changes in understanding of the people—are necessary.
In Korea, “small hydropower generation” is newly defined as hydroelectric power generation of less than 10 MW based on an amendment of the Alternative Energy Development Promotion Act established at the end of 2002 by the Korean government. Small hydropower energy has several advantages in that it is a clean existing resource that is commercially available within a construction period of one year and it has an extremely small effect on the ecosystem and environment. Additional advantages of small-scale hydropower are that it can reduce damage to water quality upstream that is caused by the installation of dams or reservoirs, and it is an important energy resource capable of achieving a significant energy generation capability within a short time as compared to other alternative energy sources. Moreover, in the case of Korea, such systems achieve a localization of more than 90%. For these reasons, the Korean government set up a long-term plan for Alternative Energy Technology Development and Supply in July 2003, and is focusing on constructing new compact hydropower plants having a total combined capacity of 500 MW by 2013.
In particular, the development of compact hydropower is suitable for countries having a high annual precipitation and extensive mountainous regions. Thus, it can be said that, in these countries, by increasing the localization ratio of systems including turbine generators and lowering manufacturing costs thereof, they have infinite possibilities in development of compact hydropower generation.
FIG. 1 shows an example of a conventional compact hydropower generation apparatus. This conventional compact hydropower generation apparatus is disclosed in Korean Patent Application No. 2003-38596 (Korean Patent Publication No. 10-2004-107916), which is entitled “SMALL HYDROPOWER GENERATION APPARATUS AND TURBINE FOR THE SAME”.
As shown in FIG. 1, the conventional small-sized hydropower generating apparatus comprises: a plurality of concrete props 10, each having an anchor bolt 12 vertically mounted therein to protrude upward, the concrete props 10 being arranged at appropriate locations determined in consideration of the geographical features of the installation site of the apparatus; a base frame 20 having an approximately plate shape and formed with a plurality of fastening holes 22 for the penetration and fixation of the anchor bolts 12; a plurality of posts 30 assembled on one side region of the base frame 20 by bolting; a turbine supported by the posts 30 by interposing bearings 32 on the posts 30, the turbine having a plurality of rotary blades 42 and which is rotated by flowing water that drops from an inlet opening 82; a supporting frame 50 assembled on the other side region of the base frame 20 by bolting; a gear box 60 assembled on the supporting frame 50 by bolting while being connected to a rotating shaft 46 of the turbine; a generator 70 assembled on the supporting frame 50 by bolting and connected to the gear box 60 by interposing a coupling 72, the generator 70 having a power transducer 74 electrically connected to a rear end thereof, and a case 80 separately assembled on the base frame 20 and having the inlet opening 82 formed at the top thereof and an outlet opening 84 to discharge the water dropping from the turbine. Not explained reference numerals 41, 43, 43a, and 87 designate a bottom plate, a facing plate, an opening, and a door, respectively.
The above described compact hydropower generation apparatus is designed to be installed near a small river, to be operated by use of flowing water having relatively low available head. In particular, the conventional apparatus has a prefabricated structure, and therefore, can be adapted for installation in many situations and exhibits an improved convenience in installation work.
However, the conventional small-sized hydropower generation apparatus has a severe problem in that it cannot secure an essential water intake source around the small river, and suffers from a structural limit in that it cannot transmit a large amount of power to the generator. For these reasons, the conventional small hydropower generation apparatus tends to fail to generate sufficient power.